#line 2 "/Users/baluteshih/coding/cplibrary/default_code.hpp"

#line 2 "/Users/baluteshih/coding/cplibrary/assumption.hpp"

#include <cassert>
#include <bits/stdc++.h>
#line 4 "/Users/baluteshih/coding/cplibrary/default_code.hpp"
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define X first
#define Y second
#define SZ(a) ((int)a.size())
#define ALL(v) v.begin(), v.end()
template <typename T>
concept PrintableContainer = requires(T& a) {
    a.begin();
    a.end();
} && !std::convertible_to<std::remove_cvref_t<T>, std::string_view>; 
template<class A, class B>
ostream& operator<<(ostream& os, const pair<A, B> &a);
template <PrintableContainer T>
std::ostream& operator<<(std::ostream& os, const T& a);
template<class A, class B>
ostream& operator<<(ostream& os, const pair<A, B> &a) {
    os << "(" << a.first << ", " << a.second << ")";
    return os;
}
template <PrintableContainer T>
std::ostream& operator<<(std::ostream& os, const T& a) {
    os << "[ ";
    bool first = true;
    for (const auto& item : a) {
        if (!first) os << ", ";
        os << item;
        first = false;
    }
    return os << " ]";
}
#ifdef bbq
#include <experimental/iterator>
#define safe cerr<<__PRETTY_FUNCTION__<<" line "<<__LINE__<<" safe\n"
#define sepline sepline_() 
#define debug(a...) debug_(#a, a)
#define orange(a...) orange_(#a, a)
void debug_(auto s, auto ...a) {
    cerr << "\e[1;32m(" << s << ") = (";
    int f = 0;
    (..., (cerr << (f++ ? ", " : "") << a));
    cerr << ")\e[0m\n";
}
void orange_(auto s, auto L, auto R) {
    cerr << "\e[1;33m[ " << s << " ] = [ ";
    using namespace experimental;
    copy(L, R, make_ostream_joiner(cerr, ", "));
    cerr << " ]\e[0m\n";
}
void sepline_(int length = 50) {
    cerr << "\e[1;35m";
    cerr << string(length, '=');
    cerr << "\e[0m\n";
}
#else
#define safe ((void)0)
#define sepline safe
#define debug(...) safe
#define orange(...) safe
#endif
void chmax(auto &x, auto val) { x = max(x, val); }
void chmin(auto &x, auto val) { x = min(x, val); }
auto floor_div(auto a, auto b) { return a / b - (a % b && (a < 0) ^ (b < 0)); }
auto ceil_div(auto a, auto b) { return a / b + (a % b && (a < 0) ^ (b > 0)); }
string bitstring(auto x, int width = -1) {
    string res;
    while (x) res.push_back((x & 1) + '0'), x >>= 1;
    if (res.empty()) res = "0";
    if (width != -1) res.resize(width, '0');
    ranges::reverse(res);
    return res;
}
vector<int> count_array(const auto &container, int sz = -1) {
    if (sz == -1) sz = *ranges::max_element(container) + 1;
    vector<int> res(sz);
    for (auto x : container) ++res[x];
    return res;
}
#line 2 "E.cpp"

#line 2 "/Users/baluteshih/coding/cplibrary/DataStructure/SegmentTree.hpp"

template<typename Value = int, typename Tag = void, bool pushdown = true>
class SegmentTree {
    static constexpr bool hasTag = !std::is_same_v<Tag, void>;
    static_assert(pushdown || hasTag, "Lazy tag must exist when pushdown is false");
    int n;
    std::vector<Value> seg;
    struct Empty {};
    [[no_unique_address]] std::conditional_t<hasTag, std::vector<Tag>, Empty> lazy;
    Value get_val(int rt) {
        if constexpr (pushdown) return seg[rt];
        else return seg[rt] + lazy[rt];
    }
    void up(int rt) {
        seg[rt] = get_val(rt << 1) + get_val(rt << 1 | 1);
    }
    void give_tag(int rt, auto tag) requires (hasTag) {
        if constexpr (pushdown) seg[rt] = seg[rt] + tag;
        lazy[rt] = lazy[rt] + tag;
    }
    void down(int rt) requires (hasTag && pushdown) {
        give_tag(rt << 1, lazy[rt]);
        give_tag(rt << 1 | 1, lazy[rt]);
        lazy[rt] = Tag();
    }
    void initialize(int l, int r, int rt, const std::vector<Value> &data) {
        if (r - l == 1) 
            return seg[rt] = data[l], void();
        int mid = (l + r) >> 1;
        initialize(l, mid, rt << 1, data);
        initialize(mid, r, rt << 1 | 1, data);
        up(rt);
    }
    Value range_prod(int L, int R, int l, int r, int rt) {
        if (L <= l && R >= r)
            return get_val(rt);
        if constexpr (hasTag && pushdown) down(rt);
        int mid = (l + r) >> 1;
        if constexpr (pushdown) {
            if (R <= mid) return range_prod(L, R, l, mid, rt << 1);
            if (L >= mid) return range_prod(L, R, mid, r, rt << 1 | 1);
            return range_prod(L, R, l, mid, rt << 1) + range_prod(L, R, mid, r, rt << 1 | 1); 
        }
        else {
            if (R <= mid) return range_prod(L, R, l, mid, rt << 1) + lazy[rt];
            if (L >= mid) return range_prod(L, R, mid, r, rt << 1 | 1) + lazy[rt];
            return range_prod(L, R, l, mid, rt << 1) + range_prod(L, R, mid, r, rt << 1 | 1) + lazy[rt];
        }
    }
    void modify(int x, int l, int r, int rt, const Value &v) {
        if (r - l == 1)
            return seg[rt] = v, void();
        if constexpr (hasTag && pushdown) down(rt);
        int mid = (l + r) >> 1;
        if constexpr (pushdown) {
            if (x < mid) modify(x, l, mid, rt << 1, v);
            else modify(x, mid, r, rt << 1 | 1, v);
        }
        else {
            if (x < mid) modify(x, l, mid, rt << 1, v - lazy[rt]);
            else modify(x, mid, r, rt << 1 | 1, v - lazy[rt]);
        }
        up(rt);
    }
    void transform(int x, int l, int r, int rt, const auto &func) {
        if (r - l == 1)
            return func(seg[rt]), void();
        if constexpr (hasTag && pushdown) down(rt);
        int mid = (l + r) >> 1;
        if (x < mid) transform(x, l, mid, rt << 1, func);
        else transform(x, mid, r, rt << 1 | 1, func);
        up(rt);
    }
    void range_transform(int L, int R, int l, int r, int rt, const auto &tag) requires (hasTag) {
        if (L <= l && R >= r)
            return give_tag(rt, tag);
        if constexpr (pushdown) down(rt);
        int mid = (l + r) >> 1;
        if (L < mid) range_transform(L, R, l, mid, rt << 1, tag);
        if (R > mid) range_transform(L, R, mid, r, rt << 1 | 1, tag);
        up(rt);
    }
    void range_transform_beats(int L, int R, int l, int r, int rt, const auto &tag, const auto &tag_condition, auto... tag_sum) requires (hasTag) {
        if (L <= l && R >= r && tag_condition([&]{ if constexpr(pushdown) return seg[rt]; else return get_val(rt) + (..., tag_sum); }()))
            return give_tag(rt, tag);
        assert(r - l > 1);
        if constexpr (pushdown) down(rt);
        else ((tag_sum = tag_sum + lazy[rt]), ...);
        int mid = (l + r) >> 1;
        if (L < mid) range_transform_beats(L, R, l, mid, rt << 1, tag, tag_condition, tag_sum...);
        if (R > mid) range_transform_beats(L, R, mid, r, rt << 1 | 1, tag, tag_condition, tag_sum...);
        up(rt);
    }
    int range_left_search(int L, int R, int l, int r, int rt, const auto &condition, auto... tag_sum) {
        if (r - l == 1) {
            if (!condition([&]{ if constexpr(pushdown) return seg[rt]; else return get_val(rt) + (..., tag_sum); }()))
                return R;
            return l;
        }
        int mid = (l + r) >> 1;
        if constexpr (hasTag && pushdown) down(rt);
        if constexpr (!pushdown) ((tag_sum = tag_sum + lazy[rt]), ...);
        if (L <= l && R >= r) {
            if (condition([&]{ if constexpr(pushdown) return seg[rt << 1]; else return get_val(rt << 1) + (..., tag_sum); }()))
                return range_left_search(L, R, l, mid, rt << 1, condition, tag_sum...);
            return range_left_search(L, R, mid, r, rt << 1 | 1, condition, tag_sum...);
        }
        int left = R;
        if (L < mid) left = range_left_search(L, R, l, mid, rt << 1, condition, tag_sum...);
        if (left == R) {
            if (R > mid) return range_left_search(L, R, mid, r, rt << 1 | 1, condition, tag_sum...);
            return R;
        }
        return left;
    }
    int range_right_search(int L, int R, int l, int r, int rt, const auto &condition, auto... tag_sum) {
        if (r - l == 1) {
            if (!condition([&]{ if constexpr(pushdown) return seg[rt]; else return get_val(rt) + (..., tag_sum); }()))
                return L - 1;
            return l;
        }
        int mid = (l + r) >> 1;
        if constexpr (hasTag && pushdown) down(rt);
        if constexpr (!pushdown) ((tag_sum = tag_sum + lazy[rt]), ...);
        if (L <= l && R >= r) {
            if (condition([&]{ if constexpr(pushdown) return seg[rt << 1 | 1]; else return get_val(rt << 1 | 1) + (..., tag_sum); }()))
                return range_right_search(L, R, mid, r, rt << 1 | 1, condition, tag_sum...);
            return range_right_search(L, R, l, mid, rt << 1, condition, tag_sum...);
        }
        int right = L - 1;
        if (R > mid) right = range_right_search(L, R, mid, r, rt << 1 | 1, condition, tag_sum...);
        if (right == L - 1) {
            if (L < mid) return range_right_search(L, R, l, mid, rt << 1, condition, tag_sum...);
            return L - 1;
        }
        return right;
    }
    Value get(int x, int l, int r, int rt) {
        [[no_unique_address]] std::conditional_t<!pushdown, Tag, Empty> tag;
        while (r - l > 1) {
            if constexpr (hasTag && pushdown) down(rt);
            if constexpr (!pushdown) tag = tag + lazy[rt];
            int mid = (l + r) >> 1;
            if (x < mid) r = mid, rt = rt << 1;
            else l = mid, rt = rt << 1 | 1;
        }
        if constexpr (pushdown) return seg[rt];
        else return get_val(rt) + tag;
    }
    void printnode(int l, int r, int rt) {
        std::cerr << "[" << l << ", " << r << "): ";
        if constexpr (hasTag) std::cerr << "val = " << seg[rt] << ", tag = " << lazy[rt];
        else std::cerr << seg[rt];
        std::cerr << "\n";
    }
    void printinfo(int L, int R, int l, int r, int rt) {
        printnode(l, r, rt);
        if (L <= l && R >= r)
            return;
        int mid = (l + r) >> 1;
        if (L < mid) printinfo(L, R, l, mid, rt << 1);
        if (R > mid) printinfo(L, R, mid, r, rt << 1 | 1);
    }
    void printall(int l, int r, int rt) {
        printnode(l, r, rt);
        if (r - l == 1) return;
        int mid = (l + r) >> 1;
        printall(l, mid, rt << 1);
        printall(mid, r, rt << 1 | 1);
    }
public:
    SegmentTree(const std::vector<Value> &data): n(data.size()), seg(n << 2) { 
        if constexpr (hasTag) lazy.resize(n << 2); 
        initialize(0, n, 1, data);
    }
    SegmentTree(int size): SegmentTree(vector<Value>(size)) {}
    Value get(int x) {
        assert(0 <= x && x < n);
        return get(x, 0, n, 1);
    }
    Value range_prod(int l, int r) {
        assert(0 <= l && r <= n);
        assert(l <= r);
        if (l == r) return Value();
        return range_prod(l, r, 0, n, 1);
    }
    void modify(int x, const Value &v) {
        assert(0 <= x && x < n);
        modify(x, 0, n, 1, v);
    }
    void transform(int x, const auto &func) {
        assert(0 <= x && x < n);
        transform(x, 0, n, 1, func);
    }
    void range_transform(int l, int r, const auto &tag) requires (hasTag) {
        assert(0 <= l && r <= n);
        assert(l <= r);
        if (l < r)
            range_transform(l, r, 0, n, 1, tag);
    }
    void range_transform_beats(int l, int r, const auto &tag, const auto &tag_condition) requires (hasTag) {
        assert(0 <= l && r <= n);
        assert(l <= r);
        if (l < r)
            range_transform_beats(l, r, 0, n, 1, tag, tag_condition);
    }
    int range_left_search(const auto &condition, int l = -1, int r = -1) {
        if (l == -1 && r == -1) l = 0, r = n;
        assert(0 <= l && r <= n);
        assert(l <= r);
        if (l == r) return r;
        return range_left_search(l, r, 0, n, 1, condition);
    }
    int range_right_search(const auto &condition, int l = -1, int r = -1) {
        if (l == -1 && r == -1) l = -1, r = n - 1;
        ++l, ++r;
        assert(0 <= l && r <= n);
        assert(l <= r);
        if (l == r) return l - 1;
        return range_right_search(l, r, 0, n, 1, condition);
    }
    void printinfo(int l, int r) {
        assert(0 <= l && r <= n);
        assert(l <= r);
        std::cerr << "\e[1;33mInfo [" << l << ", " << r << "):\n";
        if (l < r) 
            printinfo(l, r, 0, n, 1);
        std::cerr << "\e[0m\n";
    }
    void printall() {
        std::cerr << "\e[1;33mInfo all:\n";
        printall(0, n, 1);
        std::cerr << "\e[0m\n";
    }
};
#line 4 "E.cpp"

int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    int n, k, m;
    cin >> n >> k >> m, --m;
    vector<int> arr(n);
    for (int &i : arr)
        cin >> i;
    if (accumulate(ALL(arr), 0LL) % (n + 1) != 0)
        return cout << "-1\n", 0;
    if (arr[m] <= k + 1)
        return cout << "-1\n", 0;
    int mx = 0;
    for (int i = 0; i < n; ++i)
        if (i != m)
            chmax(mx, arr[i]);
    arr[m] -= 1;
    for (int i = 0; i < n; ++i) --arr[i];
    int race = accumulate(ALL(arr), 0LL) / (n + 1);
    vector<int> ans, win(n), ord(n);
    for (int i = 0; i < n; ++i) {
        if (arr[i] < race)
            return cout << "-1\n", 0;
        win[i] = arr[i] - race;
    }
    iota(ALL(ord), 0);
    ranges::sort(ord, [&](int a, int b) {
        return arr[a] > arr[b];
    });
    ans.resize(race);
    priority_queue<int> pq;
    for (int i = race - 1, j = 0; i >= 0; --i) {
        while (j < n && i + win[ord[j]] - 1 < k) {
            if (win[ord[j]] > 0) pq.push(ord[j]);
            ++j;
        }
        if (pq.empty())
            return cout << "-1\n", 0;
        ans[i] = pq.top(), pq.pop();
        if (--win[ans[i]] > 0) pq.push(ans[i]);
    }
    ans.push_back(m);
    cout << SZ(ans) << "\n";
    for (int i = 0; i < SZ(ans); ++i)
        cout << ans[i] + 1 << " \n"[i + 1 == SZ(ans)];
}